Plymouth, Mass. — A hand-carved wooden sign hanging near one front door proclaims ''Labor's Rest.'' Another, less conspicuous sign at the swimming pool across the street reads ''No children.''
While the Stars and Stripes snap sharply in the November breezes and ceramic ducks stand ceremonial guard on handkerchief-sized patios, residents rake up pine needles or take aerobic dancing lessons at the community center. A leisurely drive through South Meadow Village Mobile Home Estates here in ''America's hometown'' evokes a Sunday-afternoon kind of small-town contentment.
A couple of miles down the road, at Pinehurst Adult Mobile Home Village, the pace is equally restful. Roger Norton probably speaks for many of his neighbors when he describes the appeal of the park: ''My wife and I decided 20 years ago that when I retired we'd move into a mobile home. We'd had a travel trailer that we'd camped in all our lives, and we really loved that life style. Here there's the same sense of freedom. We know all our neighbors, but they don't drop by unless they're invited.''
Pinehurst, like the majority of mobile-home parks in the United States, is for adults 55 or over. When grandchildren come to visit, they must abide by the no-bicycling and no-skating regulations and stick close to their grandparents' homes. Pet owners are likewise clustered together in a distant section of the park, where occasional barking won't disturb the peace.
Security is a prime attraction of the park, and town police patrol the quiet streets several times a day. A notice on the manager's bulletin board urges anyone spotting an ''unknown'' to contact local authorities.
It takes about a month to order a manufactured home from the models on display at Pinehurst and have it set up. Once it's lifted off the delivery chassis and the air is let out of the tires, the work of ''buttoning up'' the various sections and attaching water and sewerage hookups begins. Attractive skirting is attached to cover the wheels, and bushes and grass are landscaped in.
While expansion continues at an almost breathless pace at Pinehurst, yet another mobile-home park is on the rise in the nearby rural town of Carver, where roadside signs advertise ''Bunnies for sale'' and the cranberry bogs are ripe for harvesting. Strollers and tricycles take the place of bird baths and pink storks here, and a German shepherd dozes on one backyard picnic table. Pine Tree Village, its developers boast, is ''the affordable alternative'' for ''young adults.''
Jackie and Patrick Brighton moved into their furnished, wall-to-wall carpeted , two-bedroom manufactured home last February. ''We were tired of paying apartment rent and we couldn't afford a house, but we still wanted something that was our own,'' Jackie explains while she feeds four-month-old Rachel. ''Here we've got land and room for a garden, and we're planning to add on a deck this summer. We're certain that we'll be here for a number of years.''
Several other young couples with toddlers now live on the street, and when Rachel is ready for kindergarten she can climb aboard a school bus right outside her front door. Best of all, Mrs. Brighton says, is the fact that their new home will be paid for in 15 years.
Retirees like Roger Norton and newlyweds like the Brightons have traditionally made up the bulk of the market for manufactured homes. For an investment of between $30,000 and $45,000 for a factory-built unit, plus a monthly park leasing fee of about $100, a buyer can have a relatively maintenance-free home with an identifiable life style.
''Retirement parks and parks that tend to have a lot of younger families have always made a lot of sense, in the same way that tracts and developments have,'' says researcher Thomas E. Nutt-Powell. ''They've created an instant sense of community.''
Dr. Nutt-Powell is author of ''Manufactured Homes: Making Sense of a Housing Opportunity'' (Boston: Auburn House. 193 pp. $21.95) and director of the Manufactured Housing Research Program at the MIT-Harvard Joint Center for Urban Studies, the only project of its kind in the US. Because of today's nationwide housing-cost crunch, he explains, another, new ''market'' of buyers now is turning to manufactured housing, as mobile homes are more correctly known. This new group includes heads of households in a middle-age group that boast generally higher incomes, more education, a broader range of employment, and a larger family size - families like the Powers of Hickory Hills Mobile Home Park in Bath, Pennsylvania.
After owning their own home in Oklahoma, the Powers moved north several years ago and started out by renting a house. ''But the rents kept going up and up and up, and we couldn't afford a home, so we decided it was time to do something else,'' says Marcella Powers. She'd often visited her mother who lives in a mobile home in Florida, and Mrs. Powers says she thought manufactured homes were ''cozy and nice - we didn't have any questions about moving into one.''
The Powers bought an unfurnished three-bedroom home where they could use most of their own furniture, and where their 16-year-old daughter Denise could have her own bedroom. Ed Powers closed in a patio on their rental lot and installed a wood-burning stove in the new room to provide more living space.
The Powers say they couldn't be happier with their new life style. Ed and Marcella are only 20 minutes from their jobs, Denise catches the school bus at the front gate, and even their toy poodle is welcome in the park.
''When we lived in a house, we knew our neighbors right next door, but that was about it,'' Mrs. Powers says. ''Here, we never come home from work that we don't blow the horn or wave to three or four people on the street. It's really home for us.''